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S )zDImplement generators for ``tensorflow`` which will balance the data.    )issparse)clone)_safe_indexingcheck_random_state   )RandomUnderSampler)Substitution)_random_state_docstring)random_stateN    F)sample_weightsampler
batch_sizekeep_sparser
   c      
         s|   t |}|dkrt|d}nt|}|| | t|dsBtd|j}||  fdd}	|	| ||||t|j	| fS )a  Create a balanced batch generator to train tensorflow model.

    Returns a generator --- as well as the number of step per epoch --- to
    iterate to get the mini-batches. The sampler defines the sampling strategy
    used to balance the dataset ahead of creating the batch. The sampler should
    have an attribute ``sample_indices_``.

    .. versionadded:: 0.4

    Parameters
    ----------
    X : ndarray of shape (n_samples, n_features)
        Original imbalanced dataset.

    y : ndarray of shape (n_samples,) or (n_samples, n_classes)
        Associated targets.

    sample_weight : ndarray of shape (n_samples,), default=None
        Sample weight.

    sampler : sampler object, default=None
        A sampler instance which has an attribute ``sample_indices_``.
        By default, the sampler used is a
        :class:`~imblearn.under_sampling.RandomUnderSampler`.

    batch_size : int, default=32
        Number of samples per gradient update.

    keep_sparse : bool, default=False
        Either or not to conserve or not the sparsity of the input ``X``. By
        default, the returned batches will be dense.

    {random_state}

    Returns
    -------
    generator : generator of tuple
        Generate batch of data. The tuple generated are either (X_batch,
        y_batch) or (X_batch, y_batch, sampler_weight_batch).

    steps_per_epoch : int
        The number of samples per epoch.
    N)r
   sample_indices_z7'sampler' needs to have an attribute 'sample_indices_'.c       	      3   s   xxt dt||D ]z}t| ||||  }t|||||  }t|rX sX| }|d krl||fV  qt|||||  }|||fV  qW qW d S )Nr   )rangelenr   r   Ztoarray)	Xyr   indicesr   indexZX_resZy_resZsw_res)r    P/var/www/html/venv/lib/python3.7/site-packages/imblearn/tensorflow/_generator.py	generatorO   s    z+balanced_batch_generator.<locals>.generator)
r   r   r   Zfit_resamplehasattr
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r   )__doc__Zscipy.sparser   Zsklearn.baser   Zsklearn.utilsr   r   Zunder_samplingr   utilsr   Zutils._docstringr	   r   r   r   r   r   <module>   s   